I ended up downloading an app called Mr Number for my phone so I could block these people.  They continually call even when I tell them the day before I have nothing to give.  

these people are so annoying. I have asked them several times not to call but they still do.

I asked to be removed from the call list and said I would call them if I had a donation. I have received numerous calls since. I will never donate to an organization that does not respect my request to not be called in my private home. I donate to organizations that don't bug me or throw it in the trash.

This was from Purple Heart asking if I had any donations for their thrift store.